ActivityThread クラスに定義された Message Codes (ソース抜粋)
android.os.Message.class のメンバに Message Code が存在する。「Message.what」である。各スレッド（クラス？）で用意した Handler にてコードの名前を任意に付けているようで、コンフリクトの心配は無いと以下にある。
public final class Message implements Parcelable {
/**
* User-defined message code so that the recipient can identify
* what this message is about. Each {@link Handler} has its own name-space
* for message codes, so you do not need to worry about yours conflicting
* with other handlers.
*/
public int what;
ActivityThread クラスでも、Activity に関係するコードについては定義がされていた。SDK-1.5 の android.jar には ActivityThread クラスが含まれておらず、残念ながら Eclipse からでは参照不可能だ。ダウンロードしたソース群から参照しよう。Activity のライフサイクル管理やメッセージ処理などが把握できるので重宝するソースかと思う。
~/frameworks/base/core/java/android/app/ActivityThread.java
--- android.app.ActivityThread.class のコード定義 ---
private final class H extends Handler {
public static final int LAUNCH_ACTIVITY = 100;
public static final int PAUSE_ACTIVITY = 101;
public static final int PAUSE_ACTIVITY_FINISHING= 102;
public static final int STOP_ACTIVITY_SHOW = 103;
public static final int STOP_ACTIVITY_HIDE = 104;
public static final int SHOW_WINDOW = 105;
public static final int HIDE_WINDOW = 106;
public static final int RESUME_ACTIVITY = 107;
public static final int SEND_RESULT = 108;
public static final int DESTROY_ACTIVITY = 109;
public static final int BIND_APPLICATION = 110;
public static final int EXIT_APPLICATION = 111;
public static final int NEW_INTENT = 112;
public static final int RECEIVER = 113;
public static final int CREATE_SERVICE = 114;
public static final int SERVICE_ARGS = 115;
public static final int STOP_SERVICE = 116;
public static final int REQUEST_THUMBNAIL = 117;
public static final int CONFIGURATION_CHANGED = 118;
public static final int CLEAN_UP_CONTEXT = 119;
public static final int GC_WHEN_IDLE = 120;
public static final int BIND_SERVICE = 121;
public static final int UNBIND_SERVICE = 122;
public static final int DUMP_SERVICE = 123;
public static final int LOW_MEMORY = 124;
public static final int ACTIVITY_CONFIGURATION_CHANGED = 125;
public static final int RELAUNCH_ACTIVITY = 126;
public static final int PROFILER_CONTROL = 127;
String codeToString(int code) {
if (localLOGV) {
switch (code) {
case LAUNCH_ACTIVITY: return "LAUNCH_ACTIVITY";
case PAUSE_ACTIVITY: return "PAUSE_ACTIVITY";
case PAUSE_ACTIVITY_FINISHING:
return "PAUSE_ACTIVITY_FINISHING";
case STOP_ACTIVITY_SHOW: return "STOP_ACTIVITY_SHOW";
case STOP_ACTIVITY_HIDE: return "STOP_ACTIVITY_HIDE";
case SHOW_WINDOW: return "SHOW_WINDOW";
case HIDE_WINDOW: return "HIDE_WINDOW";
case RESUME_ACTIVITY: return "RESUME_ACTIVITY";
case SEND_RESULT: return "SEND_RESULT";
case DESTROY_ACTIVITY: return "DESTROY_ACTIVITY";
case BIND_APPLICATION: return "BIND_APPLICATION";
case EXIT_APPLICATION: return "EXIT_APPLICATION";
case NEW_INTENT: return "NEW_INTENT";
case RECEIVER: return "RECEIVER";
case CREATE_SERVICE: return "CREATE_SERVICE";
case SERVICE_ARGS: return "SERVICE_ARGS";
case STOP_SERVICE: return "STOP_SERVICE";
case REQUEST_THUMBNAIL: return "REQUEST_THUMBNAIL";
case CONFIGURATION_CHANGED:
return "CONFIGURATION_CHANGED";
case CLEAN_UP_CONTEXT: return "CLEAN_UP_CONTEXT";
case GC_WHEN_IDLE: return "GC_WHEN_IDLE";
case BIND_SERVICE: return "BIND_SERVICE";
case UNBIND_SERVICE: return "UNBIND_SERVICE";
case DUMP_SERVICE: return "DUMP_SERVICE";
case LOW_MEMORY: return "LOW_MEMORY";
case ACTIVITY_CONFIGURATION_CHANGED:
return "ACTIVITY_CONFIGURATION_CHANGED";
case RELAUNCH_ACTIVITY: return "RELAUNCH_ACTIVITY";
case PROFILER_CONTROL: return "PROFILER_CONTROL";
}
}
return "(unknown)";
}
public void handleMessage(Message msg) {
switch (msg.what) {
case LAUNCH_ACTIVITY: {
ActivityRecord r = (ActivityRecord)msg.obj;r.packageInfo = getPackageInfoNoCheck(
r.activityInfo.applicationInfo);
handleLaunchActivity(r);
} break;
case RELAUNCH_ACTIVITY: {
ActivityRecord r = (ActivityRecord)msg.obj;
handleRelaunchActivity(r, msg.arg1);
} break;
case PAUSE_ACTIVITY:
handlePauseActivity((IBinder)msg.obj, false,
msg.arg1 != 0, msg.arg2);
break;
case PAUSE_ACTIVITY_FINISHING:
handlePauseActivity((IBinder)msg.obj, true,
msg.arg1 != 0, msg.arg2);
break;
case STOP_ACTIVITY_SHOW:
handleStopActivity((IBinder)msg.obj, true, msg.arg2);
break;
case STOP_ACTIVITY_HIDE:
handleStopActivity((IBinder)msg.obj, false, msg.arg2);
break;
case SHOW_WINDOW:
handleWindowVisibility((IBinder)msg.obj, true);
break;
case HIDE_WINDOW:
handleWindowVisibility((IBinder)msg.obj, false);
break;
case RESUME_ACTIVITY:
handleResumeActivity((IBinder)msg.obj, true,
msg.arg1 != 0);
break;
case SEND_RESULT:
handleSendResult((ResultData)msg.obj);
break;
case DESTROY_ACTIVITY:
handleDestroyActivity((IBinder)msg.obj, msg.arg1 != 0,
msg.arg2, false);
break;
case BIND_APPLICATION:
AppBindData data = (AppBindData)msg.obj;
handleBindApplication(data);
break;
case EXIT_APPLICATION:
if (mInitialApplication != null) {
mInitialApplication.onTerminate();
}
Looper.myLooper().quit();
break;
case NEW_INTENT:
handleNewIntent((NewIntentData)msg.obj);
break;
case RECEIVER:
handleReceiver((ReceiverData)msg.obj);
break;
case CREATE_SERVICE:
handleCreateService((CreateServiceData)msg.obj);
break;
case BIND_SERVICE:
handleBindService((BindServiceData)msg.obj);
break;
case UNBIND_SERVICE:
handleUnbindService((BindServiceData)msg.obj);
break;
case SERVICE_ARGS:
handleServiceArgs((ServiceArgsData)msg.obj);
break;
case STOP_SERVICE:
handleStopService((IBinder)msg.obj);
break;
case REQUEST_THUMBNAIL:
handleRequestThumbnail((IBinder)msg.obj);
break;
case CONFIGURATION_CHANGED:
handleConfigurationChanged((Configuration)msg.obj);
break;
case CLEAN_UP_CONTEXT:
ContextCleanupInfo cci = (ContextCleanupInfo)msg.obj;
cci.context.performFinalCleanup(cci.who, cci.what);
break;
case GC_WHEN_IDLE:
scheduleGcIdler();
break;
case DUMP_SERVICE:
handleDumpService((DumpServiceInfo)msg.obj);
break;
case LOW_MEMORY:
handleLowMemory();
break;
case ACTIVITY_CONFIGURATION_CHANGED:
handleActivityConfigurationChanged((IBinder)msg.obj);
break;
case PROFILER_CONTROL:
handleProfilerControl(msg.arg1 != 0, (String)msg.obj);
break;
}
}
}
